Implant for parastomal hernia

ABSTRACT

An implant for the prevention or treatment of a hernia in the proximity of an organ stoma formed in an abdominal wall includes a porous structure having a surface intended to face the abdominal cavity covered by a first film of anti-adhesive material. The porous structure includes a first part intended to be in contact with a stoma organ and having a first thickness, and a second part having a second thickness greater than the first thickness, the first part including a surface intended to face the abdominal wall covered by a second film of anti-adhesive material.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/005,131, filed Dec. 3, 2007.

BACKGROUND

1. Technical Field

The present disclosure relates to an implant suitable for use in theprevention and/or treatment of hernias that may occur in the area of astoma, particularly one formed in the abdominal wall.

2. Description of Related Art

Stomas are openings formed in a wall, for example the abdominal wall,for joining a hollow organ, for example the intestine, to the skin. Suchan operation proves necessary, for example in cases of cancer of therectum or Crohn's disease, to create an artificial anus for example,during which operation the diseased part of the intestine is resectedand the healthy intestine is exteriorized at the skin. In this case, thestoma is formed in the abdominal wall. FIG. 1 is a schematicillustration of the human digestive tract. This diagram shows thestomach 1, the small intestine 2 and the colon 3. The broken linesrepresent the part 3 a of the colon that is diseased and has beenremoved during the surgical procedure. The healthy part 3 b of the colonnow opens to the outside at the stoma 4 formed in the abdominal wall.Depending on the extent of the diseased part of the colon, the stomascan be formed in the area of the ileum 5 (ileostomy) or of the colon(colostomy), as shown in FIG. 1. Stomas can also be formed in the areaof the ureters (ureterostomy).

After operations of this kind, hernias may develop around the stoma,that is to say in the area of the peristomal wall. A weakening of thewall around the stoma may therefore result in the appearance of aparastomal hernia. To treat these parastomal hernias, prostheses areimplanted that are designed to strengthen the abdominal wall inside thepatient, in the area of the stoma. The implantation of these prosthesescan be intraperitoneal, that is to say within the actual abdominal wall,or retroperitoneal, resting against the abdominal wall.

Prostheses for treating parastomal hernias have been described in thedocument WO2004/071349. However, these prostheses are not entirelysatisfactory, particularly since they are not adapted to all types ofstomas that are formed, particularly indirect stomas.

The reason is that, for example in the case of the colon, several stomaconfigurations can be formed: the direct stoma, as shown in FIG. 2, inwhich the colon 3 issuing from the abdominal cavity 8 is perpendicularto the abdominal wall 7 and hence to the skin 6 prior to itsexteriorization, or the indirect stoma, as shown in FIG. 3, in which thecolon 3 is caused to form a bend within the abdominal cavity 8 prior toits exteriorization, the colon thus having a part 3 c parallel to theabdominal wall 7. The indirect stoma avoids a situation where theinternal part of the colon in the area of the stoma becomes invaginatedand exteriorizes.

There is therefore a need for a parastomal prosthesis able to protectthe intestine and hollow organs and to effectively strengthen theabdominal wall regardless of the type of stoma that has been formed.

SUMMARY

The present disclosure aims to meet this need by making available animplant that has specific surfaces able to protect the hollow organs,such as the intestine, regardless of the stoma that has been formed, andat the same time to effectively strengthen the abdominal wall.

The subject matter of the present disclosure is an implant for theprevention or treatment of a hernia formed in the abdominal wall in theproximity of a stoma of an organ, having a porous structure including asurface intended to face the abdominal cavity covered by a first film ofanti-adhesive material, the porous structure including a first partintended to be in contact with the stoma organ and having a firstthickness E1, and a second part having a second thickness E2 greaterthan the first thickness E1, the first part having a surface intended toface the abdominal wall covered by a second film of anti-adhesivematerial.

Thus, in the implant according to the disclosure, the first part of theporous structure, the part intended to be in contact with the stomaorgan, for example in contact with the intestine, is covered by a filmof anti-adhesive material on both of its surfaces. In one embodiment ofthe disclosure, the first and second films of anti-adhesive material arejoined to form just one film, and the first part of the porous structureis totally enclosed within the film of anti-adhesive material. As willbecome clear from the explanations given later with reference to FIGS.13 to 15, the stoma organ, for example the intestine, is protectedirrespective of whether the stoma is a direct or indirect one, becausethe part of the implant able to come into contact with it is covered bya film of anti-adhesive material.

In the present application, an “implant” is understood as abiocompatible medical device that can be implanted in the human oranimal body.

Within the meaning of the present application, the word “porous” isunderstood as the characteristic according to which a structure haspores or meshes, pockets, holes or orifices, that are open and aredistributed uniformly or irregularly and promote all cell colonization.The pores can be present in all types of configurations, for example asspheres, channels, hexagonal forms.

According to one embodiment of the disclosure, the porous structureincludes a sponge, a fibrous matrix or a combination of a sponge and ofa fibrous matrix. For example, the sponge can be obtained bylyophilization of a gel, with pores being created during thelyophilization. The fibrous matrix can be any arrangement of yarns oryarn portions creating pores between the yarns and/or yarn portions. Forexample, the fibrous matrix can be a textile, for example obtained byknitting or weaving or according to a technique for producing anonwoven.

In one embodiment of the present disclosure, the porous structure, forexample the sponge and/or the fibrous matrix, has pores with dimensionsranging from approximately 0.1 to approximately 3 mm.

In one embodiment of the present disclosure, the porous structureincludes a textile. For example, the porous structure can be composed ofa textile.

According to one embodiment of the present disclosure, the thickness E1of the first part of the porous structure ranges from approximately 0.15to 0.50 mm. A relatively small thickness of this kind allows theabdominal wall to be strengthened without any risk of damaging the stomaorgan, for example the intestine, which is in contact with the implant.

The first part of the porous structure may be a textile in the form of aknit. This knit may be a two-dimensional knit, in embodiments a knithaving a thickness less than or equal to about 5 times the mean diameterof the yarns from which it is made, for example knitted on a warpknitting machine or raschel machine with the aid of two guide barsforming a knit with two surfaces, the knit being free of sheets ofconnecting yarns between its two opposite surfaces.

When the first part of porous structure is a two-dimensional knit asdefined above, the pores are formed by the empty spaces situated betweenthe constituent yarns of the knit, for example the meshes.

The constituent yarns of the knit that form the first part of porousstructure can be chosen from among yarns made of biocompatiblematerials, bioabsorbable materials, non-bioabsorbable materials andtheir mixtures.

In the present application, the word “bioabsorbable” is understood asthe characteristic according to which a material is absorbed by thebiological tissues and disappears in vivo at the end of a given period,which can vary for example from one day to several months, depending onthe chemical nature of the material.

Thus, examples of bioabsorbable materials suitable for the yarns formingthe first part of porous structure are polylactic acid (PLA),polysaccharides, polycaprolactones (PCL), polydioxanones (PDO),trimethylene carbonates (TMC), polyvinyl alcohol (PVA),polyhydroxyalkanoates (PHA), polyamides, polyethers, oxidized cellulose,polyglycolic acid (PGA), copolymers of these materials and theirmixtures.

Examples of non-bioabsorbable materials suitable for the yarns formingthe first part of porous structure are polypropylenes, polyesters suchas polyethylene terephthalates, polyamides, polyvinylidene fluoride, andtheir mixtures.

The yarns forming the first part of porous structure of the implant can,for example, be chosen from among monofilament yarns, multifilamentyarns and their combinations. The multifilament yarn count may vary fromabout 40 to about 110 dtex. The monofilament yarns may also have adiameter from about 0.06 to about 0.15 mm.

In one embodiment of the present disclosure, the yarns forming the firstpart of the porous structure are monofilament yarns. Such monofilamentyarns may pose less risk of sepsis than do multifilament yarns. In oneembodiment of the present disclosure, the monofilament yarns are ofpolyethylene terephthalate.

A monofilament yarn suitable for the first textile part of the implantaccording to the present disclosure is, for example, a monofilament yarnwith a diameter of approximately 0.08 mm, of polyethylene terephthalate.

The porous structure of the implant according to the present disclosureincludes a second part with a thickness E2 greater than the thickness E1of the first part. The second part of the porous structure may bedesigned to act as a reinforcement of the abdominal wall.

Thus, the value of the thickness E2 of the second part of porousstructure can vary depending on the value of the thickness E1 of thefirst part of the structure, the value of the thickness E2 of the secondpart of porous structure may be greater than that of the value of thethickness E1 of the first part of porous structure. The second part ofthe porous structure may have mechanical strength superior to that ofthe first part of porous structure. For example, the second thickness E2of the second part of the porous structure can range from approximately0.40 to 3.00 mm.

As will become clear from the description that follows, the surface ofthe layer of porous structure intended to be placed facing the abdominalcavity is covered by a film of anti-adhesive material which prevents theorgans and other viscera of the abdominal cavity from attachingthemselves to the implant. This surface will be referred to hereinafteras the closed surface of the implant. By contrast, the surface of thesecond part of porous structure intended to be placed facing theabdominal wall is not covered by a film of anti-adhesive material andremains open to all cell colonization at the time of implantation. Thissurface will be referred to hereinafter as the open surface of thesecond part of the porous structure. This surface of the second part ofthe porous structure is intended to be placed resting against theabdominal wall. To permit better fixing of the implant to the abdominalwall, the open surface of the second part of porous structure caninclude fastening means, for example self-fixing ones, inherent to thissurface.

Thus, by virtue of its porous character and its thickness, the secondpart of the porous structure of the implant according to the disclosureis especially adapted to promote tissue growth via its open surfaceafter implantation. The cells of the abdominal wall deeply colonize thesecond part of the porous structure by way of its open surface placedfacing the abdominal wall.

In one embodiment of the present disclosure, the second part of theporous structure is a textile in the form of a three-dimensional knit,for example as described in applications WO99/06080 and WO99/05990, thedisclosures of which are incorporated herein by this reference in theirentirety. Within the meaning of the present application, the term“three-dimensional knit” is understood as an assembly or arrangement ofmonofilament or multifilament yarns or a combination of these, obtainedby knitting and having two opposite surfaces that are separated by athickness, in embodiments greater than or equal to about 0.50 mm, thethickness including connecting yarns and pores.

Such a three-dimensional knit can be knitted, for example, on a warpknitting machine or double-bed raschel machine with the aid of severalguide bars forming a knit that includes two opposite surfaces and aspacer. In the present application, the word “spacer” is understood asthe set or sets of yarns that connect the two surfaces of athree-dimensional knit to each other, thereby constituting the thicknessof a knit, as is described in WO99/06080 or in WO99/05990.

Thus, in the case where the second part of the porous structure is athree-dimensional knit as described above, the knitting structure candefine within the thickness of the knit a multiplicity of transversechannels or pockets that may or may not be mutually parallel. Thesepockets or channels can be interconnected and thus allow the colonizingcells to pass from one pocket or channel to another. A second part ofthe porous structure of this type promotes good tissue growth afterimplantation.

The yarns constituting the second part of the porous structure of theimplant according to the present disclosure can be chosen from amongyarns made of biocompatible materials, bioabsorbable materials,non-bioabsorbable materials and their mixtures, already listed above forthe first part of the porous structure.

Thus, examples of bioabsorbable materials suitable for the yarns formingthe second part of the porous structure are polylactic acid (PLA),polysaccharides, polycaprolactones (PCL), polydioxanones (PDO),trimethylene carbonates (TMC), polyvinyl alcohol (PVA),polyhydroxyalkanoates (PHA), polyamides, polyethers, oxidized cellulose,polyglycolic acid (PGA), copolymers of these materials and theirmixtures.

Examples of non-bioabsorbable materials suitable for the yarns formingthe second part of the porous structure are polypropylenes, polyesterssuch as polyethylene terephthalates, polyamides, polyvinylidenefluoride, and their mixtures.

The yarns forming the second part of the porous structure can, forexample, be chosen from among monofilament yarns, multifilament yarnsand their combinations. The multifilament yarn count may vary from about40 to about 110 dtex. The monofilament yarns may have a diameter of fromabout 0.06 to about 0.15 mm.

In one embodiment of the present disclosure, the yarns forming the firstpart of the porous structure are monofilament yarns. Such monofilamentyarns may pose less risk of sepsis than do multifilament yarns. Forexample, the monofilament yarns are of polyethylene terephthalate.

A monofilament yarn suitable for the second part of the porous structureof the implant according to the present disclosure is, for example, amonofilament yarn with a diameter of approximately 0.08 mm, ofpolyethylene terephthalate.

In one embodiment of the present disclosure, the second part of theporous structure has, on its open surface intended to face the abdominalwall, means of fastening the second part to the abdominal wall. Thesefastening means can be chosen from among elements that are integrallyformed on the second textile part, such as loops and barbs, or fromamong elements joined to the surface of the second textile part, such asa rough covering, hooks, threads or clips fixed on the surface of thesecond textile part.

In one embodiment of the present disclosure, the fastening means arechosen from among loops, barbs and their mixtures. In such a case, theloops and barbs can be obtained from yarns or portions of yarns that arewoven and/or knitted directly for example, with the three-dimensionalknit forming the second part of the porous structure. For example, inorder to obtain barbs, it is possible to use hot-melt yarns such as aredescribed in the application WO01/81667, the contents of which areherein incorporated by reference in its entirety.

In the embodiment of the present disclosure in which the first part ofthe porous structure is in the form of a two-dimensional knit and thesecond part of the porous structure is in the from of athree-dimensional knit, the two knits, i.e. two-dimensional andthree-dimensional, can be manufactured separately then joined togetherby at least one seam, for example, in order to form the layer of porousstructure of the implant.

In another embodiment, the two-dimensional knit and thethree-dimensional knit are knitted together on the same knitting machineand constitute a textile made in one piece, for example by usingsupplementary guide bars for the three-dimensional knit and/or differentyarn runs for producing each of the two knits. In such an embodiment ofthe present disclosure, the porous structure layer of the implantaccording to the disclosure is composed of a textile formed in onepiece, the textile having a two-dimensional zone, corresponding to thefirst part of the porous structure, and one or more three-dimensionalzones, corresponding to the second part of the porous structure. In suchan embodiment, it is possible to form a selvage at the passage from atwo-dimensional zone to a three-dimensional zone with a view to forminga smooth connection between the two parts, such that the difference inthickness between the two parts does not form a step that could damagethe biological tissue situated in the proximity of the implant.

The layer of porous structure of the implant according to the presentdisclosure is covered, on its second surface intended to face theabdominal cavity, by a first film of anti-adhesive material. Moreover,the first part of the porous structure is covered, on its surfaceintended to face the abdominal wall, by a second film of anti-adhesivematerial.

Within the meaning of the present application, the term “anti-adhesivematerial” is understood as a smooth and non-porous biocompatiblematerial that prevents the organs and other viscera of the abdominalcavity from attaching themselves to the implant.

The anti-adhesive material forming the first film can be identical to ordifferent from the material forming the second film.

In one embodiment of the present disclosure, the anti-adhesive materialconstituting the first and/or second film(s) is chosen from amongbioabsorbable materials, non-bioabsorbable materials and their mixtures.

In one embodiment of the present disclosure, the bioabsorbable materialssuitable for the first and/or second film(s) of anti-adhesive materialare chosen from among collagens, oxidized celluloses, polyarylates,trimethylene carbonates, caprolactones, dioxanones, glycolic acid,lactic acid, glycolides, lactides, polysaccharides, for examplechitosans, polyglucuronic acids, hylauronic acids, dextrans and theirmixtures.

In one embodiment of the present disclosure, the non-bioabsorbablematerials suitable for the first and/or second film of anti-adhesivematerial are chosen from among polytetrafluoroethylene, polyethyleneglycols, polysiloxanes, polyurethanes, stainless steels, derivatives ofprecious metals and their mixtures.

In one embodiment of the present disclosure, the material constitutingthe first and/or second film(s) of anti-adhesive material is ahydrophilic bioabsorbable material, which may be chosen from the groupformed by collagens, polysaccharides and their mixtures. Of thecollagens that can be used according to the present disclosure, thefollowing may be mentioned:

1) collagen whose helical structure is at least partially denatured byheat, without hydrolytic degradation, and whose method of preparation isdescribed in WO99/06080,2) native collagen, not heated, filmed with or without glycerol,crosslinked by gamma irradiation or by other chemical or physical means,3) and/or their mixtures.

Of the polysaccharides that can be used as absorbable hydrophilicmaterial according to the present disclosure, the following may bementioned: oxidized cellulose, hylauronic acid, starch, chitosan,crosslinked dextrans and/or their mixtures. All these materials arewithin the purview of persons skilled in the art. An oxidized cellulosesuitable for the present disclosure is the product sold under the brandname “Interceed®” by Ethicon. A hyaluronic acid suitable for the presentdisclosure is the product sold under the brand name “Hyalobarrier®” byFidia Advanced Biopolymers, or the product sold under the brand name“Seprafilm®” by Genzyme.

In one embodiment of the present disclosure, the first film and thesecond film form a single and unique film, the first film thencompletely coating the first part of the porous structure and thuscovering this porous structure part both on its surface intended to facethe abdominal cavity and also on its surface intended to face theabdominal wall. Thus, the first part of the porous structure is totallyenclosed in the film of anti-adhesive material before implantation andat the moment of implantation.

Thus, at the moment of implantation, and whatever the embodiment of thepresent disclosure, the two surfaces of the first part of the porousstructure are occluded by a continuous film of anti-adhesive material.

The first part of the porous structure of the implant according to thepresent disclosure, regardless of whether it is totally coated by thefirst film of anti-adhesive material or whether each of its surfaces arecovered, one by the first film of anti-adhesive material, the other bythe second film of anti-adhesive material, is thus protected at leastduring the initial phase of cicatrization, i.e. is not exposed to theinflammatory cells such as granulocytes, monocytes, macrophages, or themultinucleated giant cells that are generally activated by the surgicalprocedure. Nor is it exposed to the bacteria that may be present. Thereason for this is that, at least during the initial phase ofcicatrization, which may last approximately 5 to 10 days, only the filmor films of anti-adhesive material are accessible to the various factorssuch as proteins, enzymes, cytokines or inflammatory cells, in the firsttextile part.

In the case where the film or films of anti-adhesive material are madeof non-absorbable materials, they thus protect the first part of porousstructure before and after implantation, throughout the period ofimplantation of the implant.

Furthermore, by virtue of the film or films of anti-adhesive material,the surrounding fragile tissues, such as the hollow viscera for example,are protected in particular from the formation of severe postsurgicalfibrous adhesions.

In the case where the anti-adhesive material includes a bioabsorbablematerial, in embodiments a bioabsorbable material may be chosen that isnot absorbed until after a few days, such that the film of anti-adhesivematerial can perform its function of protecting the stoma organ, forexample the intestine, and the hollow organs during the days followingthe operation, and until the cellular recolonization of the implant inturn protects the fragile organs.

The thickness of the first anti-adhesive film may be less than thethickness E2 of the second part of the porous structure. In fact, thefilm of anti-adhesive material may not occlude the open surface of thesecond part of the porous structure, so as to permit cellularrecolonization of the second part of the porous structure afterimplantation.

The first film of anti-adhesive material may be continuous, smooth andnon-porous, covering the whole surface of the porous structure intendedto be placed facing the abdominal cavity. In one embodiment, the firstfilm of anti-adhesive material extends past the edges of the layer ofporous structure. Thus, the implant is protected from contact with theviscera. The first film of anti-adhesive material can, for example,extend past the edges of the layer of porous structure by a distanceranging from about 3 to about 10 millimetres.

The first film of anti-adhesive material may be joined to the surface ofthe layer of porous structure intended to be placed facing the abdominalcavity by means of surface penetration, keeping open the porosity on theopposite surface of the second part of the porous structure, that is tosay the open surface, intended to be placed facing the abdominal wall.

The implant according to the present disclosure can be used via thelaparoscopic route. If necessary, for example when the first and secondfilms of anti-adhesive material are made of dried collagen, the implantmay be rehydrated at the time of use, in order to make it flexible andeasier to use.

The implant according to the present disclosure can, for example, beprepared according to the following method:

a) a textile is prepared that has two-dimensional zones andthree-dimensional zones, as has been described above,b) a solution of an anti-adhesive material is prepared,c) the solution obtained at b) is poured into a mould,d) the textile is then applied to the solution, the surface of thetextile intended to face the abdominal cavity being placed on thesolution in such a way that the solution impregnates the two-dimensionalzones of the textile completely,e) it is left to dry.

With such a method it is possible to obtain an implant according to thepresent disclosure in which the first film and the second film form asingle and unique film.

Alternatively, step d) is replaced by step d′) in which the solution ofanti-adhesive material only superficially impregnates a single surfaceof the two-dimensional zones, thereby forming the first film. Theprocedure is then supplemented by an additional step in which theopposite surface of the two-dimensional zones is impregnated by the samesolution of anti-adhesive material or by another solution of anotheranti-adhesive material in order to form the second film.

Methods of covering/coating that can be used according to the presentdisclosure are described in documents WO99/06080 and WO2004/043294, thedisclosure of which are incorporated herein by this reference in theirentirety.

The implant according to the present disclosure can have any shapeadapted to the anatomy of the patient and/or to the surgical techniqueenvisaged. For example, the shape of the implant can be round, oval,square or rectangular.

In one embodiment, the implant has a generally elongate shape, forexample oval or rectangular. For example, the length of the implant maybe from about 12 to about 30 cm and its width may be from about 10 toabout 20 cm.

In another embodiment, the implant has a generally round shape. Forexample, the diameter of the implant may be from about 5 to about 20 cm.

In one embodiment of the present disclosure, the first part of theporous structure has the form of a central strip, and, for example, thewidth of the central strip may be from about 2 to about 10 cm.

In another embodiment of the present disclosure, the first part of theporous structure has the form of a disc, and, for example, the diameterof the disc may be from about 2 to about 10 cm.

In one embodiment of the present disclosure, at least one orifice isformed at the centre of the first part of the porous structure in orderto provide a passage for the stoma organ, for example the intestine,during implantation of the implant. Alternatively, at least one orificeis formed within the first part of the porous structure, the orificebeing offset relative to the centre of the implant. For certain types ofsurgery, for example ureterostomies, the implant can have two orifices.In one embodiment of the present disclosure, the orifice or orifices canbe connected to an edge of the implant by way of a slit. For example,the dimensions of the orifices may be from about 0.5 to about 8 cm. Theorifice or orifices can be offset relative to the centre of the implant.

BRIEF DESCRIPTION OF THE DRAWINGS

The principles of the present disclosure, and variants thereof, willbecome evident from the following detailed description and from theattached drawings, in which:

FIG. 1 is a schematic illustration of the human digestive tract, inwhich a stoma has been formed;

FIG. 2 is a schematic illustration of a direct stoma;

FIG. 3 is a schematic illustration of an indirect stoma;

FIG. 4 is a plan view of a first embodiment of an implant according tothe present disclosure;

FIG. 5 is a plan view of a second embodiment of an implant according tothe present disclosure;

FIG. 6 is a simplified schematic cross-sectional view of the implantfrom FIG. 4;

FIG. 7 is a photograph taken with a Hitachi S-800 FEG scanning electronmicroscope, magnification ×40, showing an embodiment of the first partof the porous structure of an implant according to the presentdisclosure;

FIG. 8 is a photograph taken with a Hitachi S-800 FEG scanning electronmicroscope, magnification ×250, showing the first part of the porousstructure from FIG. 7 once enclosed in the film of anti-adhesivematerial;

FIG. 9 is a photograph taken with a Hitachi S-800 FEG scanning electronmicroscope, magnification ×20, showing an embodiment of the second partof the porous structure of an implant according to the presentdisclosure, covered on one surface by the first film of anti-adhesivematerial;

FIGS. 10, 10A, 11 and 12 show embodiments of the knitting structuresuitable for producing a textile for an implant according to the presentdisclosure;

FIG. 13 is a cross-sectional view of an implant according to the presentdisclosure once it has been implanted after a direct colostomy;

FIG. 14 is a schematic plan view of another embodiment of an implantaccording to the present disclosure once it has been implanted after anindirect colostomy; and

FIG. 15 is a cross-sectional view of the implant from FIG. 14 along theline II in FIG. 14.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring to FIGS. 4 and 6, an implant 10 according to the presentdisclosure is shown which includes a layer of porous structure in theform of a biocompatible textile 11. As will be seen more clearly fromFIGS. 13 and 15, the layer of porous structure or textile 11 includes afirst surface 12 intended to be placed facing the abdominal wall afterimplantation, and a second surface opposite the first surface 12, thissecond surface 13 being intended to be placed facing the abdominalcavity after implantation.

As seen in FIG. 4, which is a plan view of an implant according to thepresent disclosure, the layer of porous structure includes a firsttextile part 14 and a second textile part 15, the first textile part andthe second textile part together forming the biocompatible textile 11(see FIG. 6). As seen in FIGS. 13-15 regarding the first surface 12 ofthe biocompatible textile 11, the first part 14 of textile is able tocome into contact with the intestine, and the second part 15 of textileis intended to be placed facing the abdominal wall once the implant 10according to the present disclosure is implanted in the patient.

The implant 10 shown in FIG. 4 is oval in shape. Its length may be, forexample, from about 15 to about 30 cm, and its width may be, forexample, from about 12 to about 20 cm. The shape of the implant can beadapted to the anatomy of the patient. It can also vary depending on thesurgical technique envisaged.

In one example not shown, the implant has a generally round shape. Itsdiameter may then be from about 5 to about 20 cm, for example.

Referring to FIG. 6, the implant 10 according to the present disclosureis covered on its second surface 13 by a film 16 of anti-adhesivematerial. The edge 16 a of the film of anti-adhesive material extendspast the second surface 13 of the textile 11, for example by a distanceof from about 3 to about 10 mm. Thus, the implant 10 is protected fromcontact with the viscera when it is implanted.

FIG. 6 is a simplified cross-sectional view of the implant from FIG. 4along line II. As shown in FIG. 6, the first part 14 of the textile andthe second part 15 of the textile each have a thickness, namely athickness E1 and a thickness E2, respectively. The value of thethickness E2 of the second part 15 of the textile is superior to thevalue of the thickness E1 of the first part 14 of the textile. Moreover,the film 16 completely encompasses the first part 14 of textile but onlypenetrates superficially into the thickness E2 of the second part 15 ofthe textile. It must be understood that the film 16 penetrates into thesecond part 15 of textile only by a short distance, for example by adistance corresponding to about 2% to about 10% of the thickness E2. Inthe example shown, the value of the thickness E1 is about 0.75 mm, whilethat of the thickness E2 is about 2.00 mm.

Thus, as seen in FIG. 6, the first part 14 of the textile is covered byfilm 16 of anti-adhesive material on its two surfaces, and this firstpart 14 of textile is totally enclosed within the film 16 ofanti-adhesive material.

By contrast, in regards to the second part 15 of the textile, its firstsurface 12, intended to be placed facing the abdominal wall, is notcovered by film 16 of anti-adhesive material. This surface 12 will bereferred to hereinbelow as the open surface of the second part 15 of thetextile. By contrast, the second surface 13 intended to be placed facingthe abdominal cavity, is covered by film 16 of anti-adhesive material.This surface 13 will be referred to hereinbelow as the closed surface ofthe second part of the textile. Thus, the film 16 of anti-adhesivematerial penetrates only superficially into the second part 15 of thetextile, in the area of its closed surface 13, leaving open the porosityof the first open surface 12 of the second textile part 15.

FIG. 7 shows a view of the first part 14 of textile. In this example,the first part of the textile is a knit obtained on a warp knittingmachine or raschel machine with two guide bars A and B, threadedregularly with one guide full, one guide empty, using the knittingstructure shown in FIG. 10 for bars A and B. The respective charts usedfor bars A and B are the following:

Bar A: 4-4-5-4/4-4-4-3/3-3-2-1/1-1-0-1/1-1-1-2/2-2-3-4// Bar B:1-1-0-1/1-1-1-212-2-3-4/4-4-5-4/4-4-4-313-3-2-1//

The yarn used may be a monofilament yarn of polyethylene terephthalate,having a diameter of about 0.08 mm and a titre of about 69 dtex. Theknit thus formed includes two opposite surfaces but is free ofconnecting sheets between its two opposite surfaces. It is atwo-dimensional knit according to the present application.

The thickness of the first part of the textile formed from such a knitis approximately 0.25 mm.

In the example shown, the knitting used for the first part of thetextile creates pores, in embodiments with dimensions that can rangefrom about 0.1 to about 3 mm, in embodiments from about 1.5 to about 2mm. At the moment of implantation, these pores are not visible, nor arethey accessible to tissue colonization, because the whole of the firstpart of the textile is confined in the film 16 of anti-adhesivematerial. However, after a few days, as the film of anti-adhesivematerial is absorbed and disappears after performing its function oflimiting and/or avoiding formation of adhesions during the first 10 daysfollowing the implantation operation, the pores of the first part 14 ofthe textile become accessible to tissue colonization. When a yarn ofpolyethylene terephthalate is used for producing the two-dimensionalknit, this knit is non-bioabsorbable and remains permanently at theimplantation site.

In another embodiment of the present disclosure, the first part 14 ofthe textile is made of a bioabsorbable material that is absorbed moreslowly than the bioabsorbable material constituting the film 16 ofanti-adhesive material.

As is shown in FIG. 8, which is a scanning electron microscopephotograph of a section of the implant according to one embodiment ofthe present disclosure in the area of the first textile part, the latteris enclosed in the film 16 of anti-adhesive material. The coating of thefirst part 14 of textile by the film 16 of anti-adhesive material can beeffected using any method known to a person skilled in the art. In theexample shown in FIG. 8, the first part 14 of textile is coated usingthe method described in the application WO2004/043294.

Thus, as will be seen clearly from FIG. 8, the first part 14 of thetextile is covered by the film of anti-adhesive material on its twosurfaces, and the porosity (see FIG. 7) of the first part of the textileis occluded at the moment of implantation. Thus, once covered with afilm 16 of anti-adhesive material, the two surfaces of the first part 14of textile are smooth and non-porous, as shown in FIG. 8. The twosurfaces of the first part 14 of textile do not damage the organssituated in the proximity of this first part 14 of textile, particularlythe stoma organs.

The second part 15 of the textile, of which the thickness is greaterthan that of the first part 14 of the textile, can be a knit which isobtained on a warp knitting machine or double-bed raschel machine andwhich has two opposite surfaces connected to each other by connectingyarns, that is to say a three-dimensional knit according to the presentapplication. For example, a first surface of the knit is produced withthe two guide bars A and B already mentioned above for producing thefirst part 14 of textile, these being threaded identically and with thesame charts as above. The second surface of the knit is produced withtwo supplementary guide bars D and E, threaded with one guide full, oneguide empty, using the knitting structure shown in FIG. 10 for bars Dand E. The respective charts used for bars D and E are the following:

Bar D: 0-1-1-1/1-2-2-2/3-4-4-4/5-4-4-4/4-3-3-3/2-1-1-1// Bar E:5-4-4-4/4-3-3-3/2-1-1-1/0-1-1-1/1-2-2-2/3-4-4-4//

The connection of the two surfaces can be effected, for example, byhooking one loop in two, or in three, or in four, or in five, or in sixof one of the bars D or E, whose knitting structure will be adapted. Forexample, in one embodiment of the present disclosure, the connection ofthe two surfaces is effected by hooking one loop in three of the bar E,which thus becomes bar E′, with the knitting structure shown in FIG. 10Aand according to the following chart:

Bar E′: 5-4-3-4/4-3-3-3/2-1-1-1/0-1-2-1/1-2-2-2/3-4-4-4//

In another embodiment, the connection of the two surfaces can beeffected with the aid of a fifth guide bar C, with the knittingstructure shown in FIG. 11 and according to the following chart:

Bar C: 1-0-1-0/1-1-1-1/1-1-1-1//

Thus, when the first part 14 of the textile is in the form of a centralstrip separating two lateral strips of the second part 15 of thetextile, as is shown in FIGS. 4 and 5, the textile 11 can be produced inone piece, on the same knitting machine.

With the guide bars A, B, D and E′ described above:

the whole of the first surface 13 of the textile 11 is produced with thetwo guide bars A and B,

along a first length, corresponding to the first lateral strip of thesecond part 15 of the textile, the guide bars D and E′ are threaded oneguide full, one guide empty, in order to produce the second surface ofthe three-dimensional knit forming the second part 15 of the textile,

then, along the length corresponding to the width of the central stripof the first part 14 of the textile, the guide bars D and E′ are leftempty in order to form the two-dimensional knit,

finally, along a length corresponding to the second lateral strip of thesecond part 15 of the textile, the guide bars D and E′ are againthreaded one guide full, one guide empty, in order to produce the secondsurface of the three-dimensional knit forming the second part 15 of thetextile.

In such a case, the optional fifth guide bar C is threaded only in thezones of the three-dimensional knit.

Finally, in order to obtain a smooth join between the three-dimensionalknit forming the second part 15 of the textile and the two-dimensionalknit forming the first part 14 of the textile, it is possible to use,still on the same knitting machine, a supplementary guide bar F in orderto finish the edges of the three-dimensional knits, threaded in the areaof these edges, according to the knitting structure shown in FIG. 12,using the following chart for example:

Bar F: 1-0-1-1/1-2-1-1//

A monofilament yarn may be chosen to produce the second part 15 of thetextile. This is because multifilament yarns may pose greater risks ofbacteria developing in the interstices present between the variousfilaments of the yarn.

The yarn used may be a monofilament yarn of polyethylene terephthalate,with a diameter of approximately 0.08 mm and titre of approximately 69dtex.

The thickness of the second part 15 of the textile, produced in the formof the three-dimensional knit described above, is approximately 1.50 mm.

As will be seen from FIG. 9, the second part 15 of the textile iscovered, on its surface intended to face the abdominal cavity, by thefilm 16 of anti-adhesive material. The film 16 of anti-adhesive materialpenetrates only superficially into the three-dimensional knit formingthe second part 15 of textile. Consequently, the surface of the secondpart 15 of textile intended to face the abdominal wall is open, and itsporosity is not occluded. This open surface therefore promotes allcellular growth.

The superficial covering of the surface of the second part 15 of textileintended to be placed facing the abdominal cavity can be carried outusing any method within the purview of a person skilled in the art, forexample using the method described in the application WO99/06080.

The material used for the film 16 of anti-adhesive material can, forexample, be collagen prepared in the manner described in the applicationWO99/06080.

The film 16 of anti-adhesive material may be applied to the surface ofthe textile 11 intended to be placed facing the abdominal cavity, in thefollowing way:

The solution of collagen is poured into a mould having the externaldimensions desired for the film. The textile produced above is thenapplied to this solution, at the centre of the mould, the surface to becovered being placed on the solution of collagen. The solution ofcollagen then penetrates into the textile by capillary force, completelycoating the first part of textile and covering the latter on the twoopposite surfaces of the two-dimensional knit forming it, andpenetrating only by a small distance into the thickness of the secondpart of textile, thus creating a superficial film for thisthree-dimensional part. Once the collagen has dried, the film is cutaround the textile using a scalpel.

Alternatively, the covering/coating method described in WO2004/043294can be used.

In another embodiment not shown here, the film 16 only superficiallycovers the surface of the first part of the textile, intended to beplaced facing the abdominal cavity, and does not encompass the twoopposite surfaces of this first part of the textile. In such a case, thesurface of the first part of the textile intended to be placed facingthe abdominal wall is covered with a second film of anti-adhesivematerial. Thus, each of the two opposite surfaces of the first part ofthe textile is covered by a smooth and continuous film of anti-adhesivematerial. Covering methods that can be used to form this second film arealso described in WO2004/043294.

FIG. 13 shows an implant according to the present disclosure after ithas been implanted, in the case of a direct stoma. To do this, theimplant according to the present disclosure shown in FIG. 5 is used forexample. In this figure, the reference numbers designating the sameelements as in FIG. 4 have been retained. The implant 10 in FIG. 5includes an orifice 17 which has been created at about the centre of theimplant 10 and at about centre of the central strip formed by the firstpart 14 of the textile. Such an orifice 17 can have a diameter rangingfrom about 1 to about 8 cm. A slit 18 starting from the central orifice17 and opening out on an edge of the implant 10 allows the implant to beadjusted around the colon 3 during implantation of the implant.

In one embodiment not shown here, the orifice 17 is offset relative tothe centre of the implant 10. It is also possible to have severalorifices, depending on the surgery envisaged.

Thus, in FIG. 13, an implant 10 similar to that in FIG. 5 has beenplaced around the colon 3, which is at substantially right angles to theabdominal wall 7 and to the skin 6. As shown in this figure, the firstpart 14 of the textile is covered entirely, that is to say on its twoopposite surfaces, by the film 16 of anti-adhesive material is situatedin direct proximity to the colon 3. Thus, the colon 3, which is afragile organ, is not damaged by the implant 10. The open surface of thesecond part 15 of the textile, which is porous and promotes cellularrecolonization, is situated facing the abdominal wall 7. Thus, afterimplantation, the cells of the abdominal wall can gradually colonize thesecond part 15 of textile, for example the three-dimensional knitforming it.

It is possible to fix the implant 10 to the abdominal wall 7 usingstaples or sutures. In addition, or alternatively, the open surface ofthe second part 15 of the textile can intrinsically include barbs orloops, which will facilitate its natural attachment to the abdominalwall. Such an affixing knit is described in the application WO01/81667.

Finally, the second surface of the textile, completely covered by film16 of anti-adhesive material, is situated facing the abdominal cavity 8.Thus, the hollow and fragile organs, the viscera, are not damaged by theimplant.

FIGS. 14 and 15 show an implant according to the present disclosureafter it has been implanted, in the case of an indirect stoma. To dothis, the implant according to the present disclosure in FIG. 4 is used,for example. FIG. 14 shows a plan view of the implant 10 according toFIG. 4 at its implantation site in the area of the colon 3. For greaterclarity, the skin and the abdominal wall have not been depicted. As willbe seen from FIG. 15, which is a cross-sectional view of FIG. 14 alongline II-II and in which the abdominal wall 7 and the skin 6 have beendepicted, the colon 3 forms a bend prior to exteriorization, and theimplant 10 is placed inside this bend. A part 3 c of the colon is thussituated between the implant 10 and the abdominal wall 7.

As will be seen from these two figures, the part 3 c of the colon facesand is able to come into contact with the first part 14 of the textilecovered on its two opposite surfaces by the film 16 of anti-adhesivematerial. Thus, neither the part 3 c of the colon, situated between theimplant 10 and the abdominal wall 7, nor the part 3 d of the coloncorresponding to the second length of the bend and able to lie under theimplant 10 in the area of the abdominal cavity 8, risks being damaged bythe implant 10. This is because the parts 3 c and 3 d of the colon 3 areeach facing a surface of the first part 14 of textile covered by a film16 of anti-adhesive material. Moreover, the relatively small thicknessE1 of this first part 14 of textile permits flexible and atraumaticsupport of the colon 3.

In an indirect stoma of this kind, the implant 10 may act like a hammockfor the part 3 c of the colon 3, and the implant 10 can be fixed to theabdominal wall 7 via the open surface of the second part 15 of thetextile placed facing the abdominal wall 7.

The present disclosure also relates to a method for treatment orprevention of a hernia in the proximity of a stoma formed in the skin,including the step of implanting an implant of the type described abovein the area of the stoma. In one embodiment of the present disclosure,the implant is fixed to the abdominal wall. The implant described abovecan be implanted by open surgery or by laparoscopy.

The implant according to the present disclosure is used in particular inthe treatment of parastomal hernias. It is able to support and/orprotect the organs that are to be treated, such as the colon or ureters,without damaging them, while at the same time effectively strengtheningthe wall in which the stoma is formed, such as the abdominal wall,irrespective of the type of stoma formed, i.e. direct stoma or indirectstoma.

1-39. (canceled)
 40. A method of treating or preventing a hernia in theproximity of a stoma formed in the skin comprising: implanting a porousstructure in the proximity of a stoma, the porous structure including asurface intended to face an abdominal cavity covered by a first film ofanti-adhesive material, the porous structure comprising a first partintended to be in contact with a stoma organ and having a firstthickness, and a second part having a second thickness greater than thefirst thickness, the first part including a surface intended to face anabdominal wall covered by a second film of anti-adhesive material.
 41. Amethod of forming an implant for the prevention or treatment of a herniaformed in an abdominal wall in the proximity of a stoma of an organcomprising: preparing an implant having a porous structure composed of atextile having a two-dimensional zone corresponding to a first part ofthe porous structure and one or more three-dimensional zonescorresponding to a second part of the porous structure; pouring asolution of anti-adhesive material into a mould; applying the first partof the porous structure on the solution such that the solution at leastsuperficially impregnates a single surface of the two-dimensional zone;and drying the porous structure.
 42. The method according to claim 41,wherein the step of applying the first part of the porous structure onthe solution further comprises substantially completely impregnating thetwo-dimensional zone with the solution.
 43. The method according toclaim 41, wherein the step of applying the first part of the porousstructure on the solution further comprises applying the one or morethree-dimensional zones corresponding to the second part of the porousstructure on the solution such that the solution at least superficiallyimpregnates a single surface of the one or more three-dimensional zones.44. The method according to claim 41, further comprising the step ofapplying the solution to a second surface opposite the single surface ofthe two-dimensional zone corresponding to a first part of the porousstructure.
 45. The method according to claim 41, wherein preparing theimplant includes knitting at least one yarn to form the textile.
 46. Themethod according to claim 41, wherein preparing the two-dimensional zonecorresponding to the first part of the porous structure includesknitting at least one yarn using two-guide bars A and B according to thefollowing pattern: Bar A:4-4-5-4/4-4-4-3/3-3-2-1/1-1-0-1/1-1-1-2/2-2-3-4// Bar B:1-1-0-1/1-1-1-2/2-2-3-4/4-4-5-4/4-4-4-3/3-3-2-1//.
 47. The method ofclaim 46, wherein the at least one yarn of the two-dimensional zonecorresponding to the first part of the porous structure includes amonofilament yarn including polyethylene terephthalate.
 48. The methodaccording to claim 46, wherein preparing the one or morethree-dimensional zones corresponding to the second part of the porousstructure includes knitting at least one yarn using two-guide bars D andE according to the following pattern: Bar D:0-1-1-1/1-2-2-2/3-4-4-4/5-4-4-4/4-3-3-3/2-1-1-1// Bar E:5-4-4-4/4-3-3-3/2-1-1-1/0-1-1-1/1-2-2-2/3-4-4-4//.
 49. The method ofclaim 48, wherein the at least one yarn of the one or morethree-dimensional zones corresponding to the second part of the porousstructure includes a monofilament yarn including polyethyleneterephthalate.
 50. The method according to claim 48, wherein preparingthe implant further includes connecting the two-dimensional zonecorresponding to a first part of the porous structure to the one or morethree-dimensional zones corresponding to the second part of the porousstructure via knitting at least one additional yarn using a single guidebar C according to the following pattern: Bar C:1-0-1-0/1-1-1-1/1-1-1-1//.
 51. The method according to claim 46, whereinpreparing the one or more three-dimensional zones corresponding to thesecond part of the porous structure includes knitting at least one yarnusing two-guide bars D and E′ according to the following pattern: Bar D:1-1-1-1/1-2-2-2/3-4-4-4/5-4-4-4/4-3-3-3/2-1-1-1// Bar E′:5-4-3-4/4-3-3-3/2-1-1-1/0-1-2-1/1-2-2-2/3-4-4-4//.
 52. The method ofclaim 51, wherein the at least one yarn of the second part includes amonofilament yarn including polyethylene terephthalate.
 53. The methodof claim 41, wherein preparing the implant includes a textile whereinthe two-dimensional zone corresponding to the first part of the porousstructure is a central strip separating two lateral strips of thethree-dimensional zones corresponding to the second part of the porousstructure.
 54. The method of claim 41, wherein preparing the implantincludes a textile wherein the two-dimensional zone corresponding to thefirst part of the porous structure has a first thickness and the one ormore three-dimensional zones corresponding to the second part of theporous structure has a second thickness greater than the firstthickness.
 55. The method of claim 41, wherein preparing the implantincludes a textile wherein the one or more three-dimensional zonescorresponding to the second part of the porous structure includes asecond surface intended to face the abdominal wall having elementschosen from loops, barbs, hooks, threads, or clips for fastening thesecond part to the abdominal wall.
 56. The method of claim 41, whereinpouring the solution of anti-adhesive material into the mould includes asolution which includes materials chosen from among collagens, oxidizedcelluloses, polyarylates, trimethylene carbonates, caprolactones,dioxanones, glycolic acid, lactic acid, glycolides, lactides,polysaccharides, chitosans, polyglucuronic acids, hylauronic acids,dextrans, polytetrafluoroethylene, polyethylene glycols, polysiloxanes,polyurethanes, stainless steels and their mixtures.
 57. The method ofclaim 41, wherein pouring the solution of anti-adhesive material intothe mould includes a solution which includes materials chosen fromcollagens, chitosans, and their mixtures.
 58. The method of claim 41,wherein applying the first part of the porous structure on the solutionsuch that the solution extends past an edge of the porous structure. 59.The method of claim 41, wherein preparing the implant further includes atextile including at least one orifice formed at about center of thefirst part of the porous structure to provide a passage for the stomaorgan during implantation of the implant.
 60. The method of claim 41,wherein preparing the implant further includes a textile including atleast one orifice being offset relative to the center of the implant.